Method of reducing ores.



R. S. WILE- METHOD OF REDUCING ORBS.

APPLICATION FILED DEO.15, 191s.

Patented Sept. 22, 191% 7 e Ks (A;

WITH ESSES 50, being out of contact wi packing of coke or cha'rcoa'lis needed;

around the electrodes, because the heat is generated'in the sla This heat is, there I RAYMOND S. WILE, OF PITTSBURGH, PENNSYLVANIA.

METHOD or REDUCING onus.

To all whom it may concern.

Be it known that I, RAYMOND S. WEE, a citizen of the United States, residing at Pittsburgh, in the county of Allegheny and State of Pennsylvania, have invented a new and useful Improvement in Methods of Reducing Ores, of which the following is a full, clear, and-exact description, reference being had to the accompanying drawing, forming part of this specification, in which the figure is a vertical central section showing one form of apparatus for carrying out my invention.

My invention relates to the reduction of ores and is designed to provide a cheap and efficient electric method by which ores may be reduced to mattes, metals, orother elements or compounds. v

One object of my invention liesin doing away with the difiiculty arising in such furnaces owing to the varying resistance in the coke, charcoal, or other fuel surrounding the electrodes.

Another object is to retard the rapid destruction of the electrodes and their break- IA still further object is to obtain a more uniform heat and consequently more regular action of the furnace.

Heretofore in such furnaces, particularly.

those used for iron smelting, for which my invention is especially designed, the shaft or stack portion of the furnace is provided i;ing i n the crucible a deep bath of molten slag, which is maintained therein; the upper ielectrodes contacting with this slag while fore, much more uni orm. The wear on the electrodes is greatly reduced, and uniform action of the furnace obtamed.

Specification of Letters Patent.

reduced material.

the charge. No

Patented Sept. 22, 1914.

Application filed December 15, 1913. Serial No. 806,692.

In the drawings in which I show one form of furnace for carrying out my invention,

2 represents the shaft or stack portion of the furnace, which may be of any desirable type, and 3 the enlarged crucible into which the charge descends from the stack. I have shown three electrodes, the upper two 4:, 45 of which project in through holes in" the roof of the crucible and may be adjusted by the rack and pinion mechanism shown at 5-.

The lower electrode 6 projects through the bottom of the crucible and contacts with the Any number of electrodes may, of course, be used, either in the top or the bottom. p

I may employ different types of electric current. For example, in the form shown, I may use a three-phase current, one phase connected to each electrode; or I may use a two-phase current, each of the upper electrodes being connected to one phase, and the lower electrode to a common return conductor.

In the upper part of the crucible, near itsconnection with the shaft, is provided a slag outlet 7, and a tap-hole 8 is provided for the reduced material from the bottom through the side of the crucible. Twyers 9 are pro vided in the bosh of the shaft through which air may be blown in, if desired to burn the carbon-monoxid rising from the charge of ore, coke or other fuel and flux.

In starting the furnace, I first lower the upper electrodes until they contact with some conducting material in the bottom of the crucible, so that the current will flow and melt this material. The slag forming material is gradually filled in and the electrodes gradually raised until'the crucible is practically full of molten slag bath. The charge in the stack descends into this bath as reduction occurs, and the reduction continues through the stack and crucible. The

molten reduced material collects at the bot-- hole at the'top of the crucible to keep the bath at a: practically constant depth.

Asz'the upper electrodes enter the crucible only a small distance, they aresubjected't'o'the' gases to only a slight extent, and hence their life is relatively long. The

is no chemical action between the two and no pressure from the charge on the electrodes tending to break them.

Little manipulation of the electrodes is required as they will wear very slowly. The operation goes on continuously, the charge being supplied at the top of the stack and the reduced material being tapped out at the bottom of the crucible.

The advantages of my inyention' result from using a deep slag bath, keeping the charge away from the electrodes, and also giving a uniform temperature throughout the smelting operation.

By the term deep bath, as used herein and in the claims, I refer to a bath whose depth is a matter of feet, rather than inches, That is to say, in no case should the bath be less than one and one-half feet in depth, and is preferably three feet or more in depth. The exact depth, of course, will depend upon the size and particular character of the furnace, but in all cases, it should be in excess of the diameter of the feed-in-opening for the charge. By the use of a deep bath of this character, I am able to use an electric current of much higher voltage than has heretofore been possible, thereby enabling me to keep the slag much hotter and at a more uniform temperature. This deep bath also effects a much more complete separation of the metals from the slag.

The most important feature of my invention lies in the small consumption of electrodes, thus greatly reducing the cost of operation. The process also allows the use of any carbonaceous material for the reduction of the charge; this, of course, being mixed with the, charge as it is needed, in the usual manner. a

The apparatus may be varied widely, different kinds of current may be used, the electrodes may project through the sides of the crucible, and other changes may be made without departing from my invention.

Iclaim:

1. The method of reducing ores, which consists in forming a deep bath of slag,

feeding ore downwardly into said bath,

passing an electric current through the bath between separated electrodes, and maintaining the bath at an approximately constant depth greater than the diameter of the feed-in-opening and at a level which surrounds and protects those portions of the upper electrodes which are within the furnace; substantially as described.

2. The method of reducing ores, which consists in forming a deep bath of slag, feeding ore downwardly into said bath,

-passing a multi-phase electric current through the bath in different directions between electrodes to thereby maintain an ap proximately uniform temperature throughout the bath, and maintaining the bath'at an feeding an ore charge downwardly into the bath, passing a niulti-phase electric current through the bathin different directions between electrodes, and positioning and adjusting the electrodes to cause the different current paths through the bath to have approximately the same resistance; substantially as described.

4:. The method of reducing ores, which consists in forming a deep slag bath within a ,crucible, andsubstantially filling the crucible, passing an electric current through the bath between upper and lower electrodes. and when the bath has been properly formed, adjusting the upper electrodes to a position in which they dip within the surface portion only of the body of the bath. maintaining the bath at a substantially constant depth and at-a level which causes it to surround and protect the portions of the electrodes which are within the crucible, and during the operation feeding ores into the bath out of contact with the electrodes; substantially as described.

5. The method of reducing ores, which consists in maintaining a comparatively deep slag bath, passing an electric current through the bath between electrodes, and feeding an ore charge down into the bath out of contact with the electrodes, the bath having a greater cross sectional area than the cross sectional area of the downwardly feeding ore-eharge and maintaining said bath at adepth which is also greater than the diameter of the feed-.in-opening for the ore charge; substantially as described.

6'. The method of reducing ores, which consists in maintaining a comparatively deep slag bath, passing an electric current through the bath between a plurality of upper electrodes and one or more lower electrodes, and feeding an ore charge down into the bath out of contact'with and intermediate the upper electrodes and maintaining the bath at such a level as to completely surround and protect those portions of the upper electrodes which are within the furnace; substantially as-described.

7. The method of reducing ores, which consists 1n maintaining a comparatively deep slag bath and passing a three-phaseilgg;

electric current through the bath between three substantially equi-distant electrodes, some of which project slightly into the up-' per portion of the bath; substantially as described.

8. The method of reducing ores, which consists in forming a deep slag bath Within a crucible, maintaining said bath at an approximately constant depth' by passing an electric current therethrough between electrodes, and feeding an ore charge down into the bath out of contact With the electrodes; substantially as described.

-' maintain the bath at a substantially con stant depth and at a level Which causes it at all times to completely surround and protect the portions of the upper electrodes which are Within the furnace; substantially as described. L 10. The method of reducing ores, which consists in maintaining a comparatively deep slag bath, passing an electric current through the bath between electrodes, feeding an ore charge down into the bath out of contact with the electrodes, and maintaining said bath at a depth which is greater than the diameter of the feed-in opening for the ore charge; substantially as described.

11. The method of reducing ores, which consists in maintaining a comparatively deep slag bath and passing a three-phase electric current through the bath between three substantially equidistant electrodes, some of which project slightly into the up per portion of the bath, and feeding ore.

into said bath out of contact with the upper electrodes; substantially as described.

In testimony whereof, I have hereunto set my hand.

RAYMOND S. WILE. Witnesses:

GEO. B. BLEMING, FRANCES BEoKET'r. 

